1. Field of the Invention
The present invention relates to a coupler joint which can be interposed between a dialyzer connector and a coupler of dialysis apparatus when the connector and the coupler are to be connected to each other.
2. Description of the Related Art
Numerous people have recently been forced to undergo artificial dialysis owing to kidney dysfunction or the like. Artificial dialysis serves a part of the role of the kidneys, eliminating wastes from blood and adjusting water content, electrolytes and pH. In almost all artificial dialysis which is currently performed, hollow fiber dialyzers are used, and a dialyzer is connected to a dialysis apparatus which monitors and controls artificial dialysis. Blood flows inside approximately ten thousand hollow fibers which are charged in the dialyzer, while a dialysis solution flows outside the hollow fibers. Two solution supplying/discharging tubes which supply and discharge the dialysis solution to and from the dialyzer extend from the dialysis apparatus, and the tip of each of these solution supplying/discharging tubes is provided with a coupler to be connected to a connector which is a dialysis solution outlet/inlet for the dialyzer.
The dialyzer connector 21 shown in FIG. 2 has a shape determined by international standards (ISO8637). And-the coupler which is connected to this connector, as shown in FIG. 3, has a plurality of components such as an O-ring 40, ball bearings 50 and a spring 80.
The dialyzer is disposable and is abandoned after the completion of artificial dialysis, but the dialysis solution circulating tubes and the coupler provided in the dialysis apparatus are cleaned and sterilized, and are repeatedly reused. However, this coupler, as mentioned above, is made of a plurality of components such as ball bearings and an O-ring, so that gaps are inevitably formed between the components, and dialysis solution enters these gaps during artificial dialysis. As shown in FIG. 5, the dialysis solution particularly easily enters the gap between the O-ring 40 and a concave groove 32, and if the dialysis solution in this portion is not fully cleaned during cleaning, bacteria are likely to propagate in this portion. Then, there is a risk that endotoxin produced by these bacteria enters the dialysis solution during dialysis and this endotoxin enters a blood of a patient being dialyzed.
To solve this problem, a seal position connecting a dialyzer connecter with a coupler during dialysis and a seal position connecting an adapter with the coupler during cleaning and sterilizing of the dialysis apparatus have been modified in a prior invention. (See Japanese laid-open publication No. JP 9-51945 A).
However, the coupler and the adapter described in JP 9-51945 A have exclusive special shapes, and cannot have the desired effect without such combination. Accordingly, if it is used in an incorrect combination, there is a risk that complete cleaning and sterilization cannot be effected.